Escola Politécnica

Formando engenheiros e líderes

 

 

O professor Michele Serpilli, da Università Politecnica delle Marche, da Itália, apresentará o seminário de pesquisa “Imperfect contact laws in multiphysics composites” na quarta, dia 19 de fevereiro, às 14h, na sala S-28 do prédio da Engenharia Civil da Poli. O evento é organizado pelo grupo que coordena o Projeto Temático em Dinâmica não linear: Centro de dinâmica não linear aplicada à engenharia.

 

Abstract

In the last decades, the interest in bonded structures, obtained by assembling different parts made of possibly different materials to compose a unique structure, is strongly increased. The advantage of such composites is that their mechanical performances and properties are designed to be superior to those of the constituent materials acting independently. In the present study, the attention is focused on a specific type of composite, constituted by two media, called the adherents, bonded together with a thin interphase layer, called the adhesive. The composite constituents are made of different linear multiphysic materials with highly contrasted constitutive properties. The study considers a generic multiphysic coupling in a very general framework and can be adapted to well-known multiphysic behaviors, such as piezoelectricity, thermo-elasticity, flexoelectricity and any other higher order continuum theories, such as micropolar or strain gradient elasticity. The analysis has been carried out by means of asymptotic expansions method. By defining a small parameter ε, associated with the thickness and constitutive properties of the middle layer, an asymptotic analysis is performed. The middle layer thickness depends linearly on ε, while the multiphysic stiffness ratios between the adherents and the adhesive depend on εp. Three different limit models and their associated limit problems are characterized: the soft interface model, in which the constitutive coefficients depend linearly on ε; the hard interface model, in which the constitutive properties are independent of ε; the rigid interface model, in which they depend on 1/ε. The asymptotic expansion method is reviewed by taking into account the effect of higher order terms and by defining a general multiphysic interface law which comprises the above aforementioned models. Finally, some numerical examples are given in order to show the efficiency of the proposed methodology in the case of piezoelectric and thermo-mechanical couplings. The numerical investigations are performed in the framework of the finite element method. In particular, finite elements are introduced to solve the fully 3D initial problem, considering a three-phase composite, and the limit 3D-2D problem with two layers with imperfect interface transmission conditions.

 

Short bio

Michele Serpilli obtained the five-year Master of Sciences in Civil Engineering with full marks at the Polytechnic University of Marche (UNIVPM) in 2005 and earned the PhD Degree in “Mécanique et Génie Civil” at University of Montpellier 2, France, during the academic year 2005-2008. He is now Associate Professor of Solids and Structural Mechanics at the Department of Civil and Building Engineering, and Architecture at UNIVPM. He developed research and teaching activities at the Universities of Ancona, Marseille, La Havana, and ISAE SupMéca Paris. He is the author and co-author of more than 50 refereed scientific papers published in International Journals and Conferences. He is a reviewer of research projects for some International Institutions and reviewer of many International Journals. Member of the scientific committee of several International Conferences and he is a member of the Editorial Boards of different International Journals. His research interests focus on mathematical model for laminated beams and plates, composite materials, interface and contact problems in multiphysics frameworks, asymptotic methods, experimental and numerical analysis of sustainable materials and structures, numerical models for floating offshore wind turbines.